Platinum alloy and method of production thereof

Abstract

The disclosure relates to a platinum alloy comprising (a) 63.01 to 69.99 wt. % of platinum, (b) 1.5 to 10 wt. % of cobalt, and (c) 20.01 to 35.49 wt. % of copper. The platinum alloys have excellent mechanical and optical properties for use in the production of ornamental articles such as rings, necklaces, earrings, watch bands, watch bodies and other jewelry. The disclosure further relates to a method of preparing the platinum alloys and their use in the production of ornamental articles. Still further the disclosure relates to ornamental articles comprising the platinum alloy and a method of production thereof.

1 . A platinum alloy comprising:
 63.01 to 69.99 wt. % of platinum,   1.5 to 10 wt. % of cobalt, and   20.01 to 35.49 wt. % of copper.   
   
   
       2 . The platinum alloy of  claim 1 , wherein said alloy has a substantially crystalline structure. 
   
   
       3 . The platinum alloy of  claim 1 , wherein said alloy comprises 63.5 to 66.5 wt. % of platinum. 
   
   
       4 . The platinum alloy of  claim 1 , wherein said alloy comprises 64 to 66 wt. % of platinum. 
   
   
       5 . The platinum alloy of  claim 1 , wherein said alloy comprises about 65 wt. % of platinum. 
   
   
       6 . The platinum alloy of  claim 1 , wherein said alloy comprises 2.0 to 6.0 wt. % of cobalt. 
   
   
       7 . The platinum alloy of  claim 6 , wherein said alloy comprises 2.5 to 5.5 wt. % of cobalt. 
   
   
       8 . The platinum alloy of  claim 1 , wherein said alloy further comprises 0.001 to 2 wt. % of at least one first metal selected from the group consisting of iridium and ruthenium. 
   
   
       9 . The platinum alloy of  claim 1 , wherein said alloy further comprises 0.001 to 2 wt. % of at least one second metal selected from the group consisting of indium and gallium. 
   
   
       10 . The platinum alloy of  claim 1 , wherein said alloy further comprises 0.001 to 5 wt. % of palladium. 
   
   
       11 . The platinum alloy of  claim 1 , wherein said alloy further comprises 0.001 to 0.5 wt. % of silicon. 
   
   
       12 . The platinum alloy of  claim 11 , wherein said alloy comprises 0.1 to 0.3 wt. % of silicon. 
   
   
       13 . The platinum alloy of  claim 1 , wherein said alloy further comprises 0.001 to 0.5 wt. % of zirconium. 
   
   
       14 . The platinum alloy of  claim 13 , wherein said alloy comprises 0.1 to 0.3 wt. % of zirconium. 
   
   
       15 . The platinum alloy of  claim 1 , wherein the total amount of other elements present in said platinum alloy besides Pt, Cu, and Co does not exceed 10 wt. %, based on the total weight of said platinum alloy. 
   
   
       16 . The platinum alloy of  claim 15 , wherein the total amount of other elements present in said platinum alloy besides Pt, Cu, and Co does not exceed 7.5 wt. %, based on the total weight of said platinum alloy. 
   
   
       17 . The platinum alloy of  claim 1 , wherein the total amount of phosphorous present in said platinum alloy is less than about 2.0 wt. % based on the total weight of said platinum alloy. 
   
   
       18 . The platinum alloy of  claim 1  consisting essentially of:
 63.5 to 67.5 wt. % of platinum,   1.5 to 8 wt. % of cobalt, and   24.5 to 35 wt. % of copper,   
     wherein copper may substituted by one or more of the following elements in the amounts specified:
 0.001 to 2 wt. % of at least one of said first metals selected from the group consisting of iridium and ruthenium; 
 0.001 to 2 wt. % of at least one of said second metals selected from the group consisting of indium and gallium; 
 0.001 to 5 wt. % of palladium; 
 0.001 to 0.5 wt. % of silicon; and/or 
 0.001 to 0.5 wt. % of zirconium. 
 
   
   
       19 . The platinum alloy of  claim 1 , wherein the tensile strength of said alloy is in the range of 450 to 800 N/mm 2 . 
   
   
       20 . The platinum alloy of  claim 1 , wherein the Vickers hardness of said alloy, measured at soft state, is in the range of 130 to 210 HV10. 
   
   
       21 . The platinum alloy of  claim 1 , wherein the elongation at break of said alloy is at least 20%. 
   
   
       22 . The platinum alloy of  claim 1 , wherein the color tone of said alloy corresponds essentially to the platinum white color tone of a PtCu950 alloy. 
   
   
       23 . A method of preparing an alloy according to  claim 1 , which comprises (a) blending the components of the alloy; and (b) melting the alloy. 
   
   
       24 . A platinum-colored material for ornamental purposes comprising a platinum alloy according to  claim 1 . 
   
   
       25 . An ornamental article comprising the platinum alloy of  claim 1 . 
   
   
       26 . The ornamental article of  claim 25 , wherein said ornamental article is a ring, a necklace, an earring, a watch band, a watch body or other jewelry. 
   
   
       27 . A method of fabricating the ornamental article of  claim 26 , which comprises forming the ornamental article from an alloy according to  claim 1 . 
   
   
       28 . The method of  claim 27 , wherein the alloy is casted into the shape of the ornamental article. 
   
   
       29 . The method of  claim 28 , wherein the ornamental article is a ring, a necklace, an earring, a watch band, a watch body or other jewelry. 
   
   
       30 . The platinum alloy of  claim 18 , wherein the tensile strength of said alloy is in the range of 450 to 800 N/mm2. 
   
   
       31 . The platinum alloy of  claim 30 , wherein the Vickers hardness of said alloy, measured at soft state, is in the range of 130 to 210 HV10. 
   
   
       32 . The platinum alloy of  claim 18 , wherein the elongation at break of said alloy is at least 20%. 
   
   
       33 . The platinum alloy of  claim 18 , wherein the color tone of said alloy corresponds essentially to the platinum white color tone of a PtCu950 alloy. 
   
   
       34 . A method of preparing an alloy according to  claim 18 , which comprises (a) blending the components of the alloy; and (b) melting the alloy. 
   
   
       35 . A platinum-colored material for ornamental purposes comprising a platinum alloy according to  claim 18 . 
   
   
       36 . An ornamental article comprising the platinum alloy of  claim 18 . 
   
   
       37 . The ornamental article of  claim 36 , wherein said ornamental article is a ring, a necklace, an earring, a watch band, a watch body or other jewelry. 
   
   
       38 . A method of fabricating the ornamental article of  claim 36 , which comprises forming the ornamental article from an alloy according to  claim 18 . 
   
   
       39 . The method of  claim 38 , wherein the alloy is casted into the shape of the ornamental article. 
   
   
       40 . The method of  claim 39 , wherein the ornamental article is a ring, a necklace, an earring, a watch band, a watch body or other jewelry.